Issue with Reading two Int values from a file

Question

I have file with the below data

A,8,43
B,7,42,
C,9,34

I am using the below code to read the data

Scanner input = new Scanner(new File("D:\\test.txt"));
input.useDelimiter(",|\n");  
while(input.hasNext()) {
   String name = input.next();
   int age = input.nextInt();
   int height = input.nextInt();

When I am executing the program I am getting InputMisMatch exception, Please suggest what is mistake.

Answer 1

At end of second line you have , and line separator (I am assuming \n) This means you have empty element between these two delimiters.

So in third iteration

String name = input.next();  
int age = input.nextInt();
int height = input.nextInt();

input.next(); is consuming "", which means input.nextInt() will try to consume C.

To solve this problem you can set delimiter to be combination of one or more commas and line separators like

input.useDelimiter("(,|\n)+");

To improve your code even farther instead of \n you can use \\R added in Java 8 (or \r|\n in earlier versions) to handle all line separators, because currently you don't consider \r as delimiter so it can be treated as valid token.

So better solution would be using

input.useDelimiter("(,|\\R)+"); //for readability

or even

input.useDelimiter("[,\r\n]+");